In an asynchronous DS-CDMA system of multiple users, there are inter-symbol interference(ISD , multiple access interference(MAI) and external interference(EI). According to function space theory, decomposing the narrowband external interference on a function space with finite dimensions,regarding each basis of the function space as a vector of the mixing matrix,and taking the coefficient of corresponding basis as one of sources, we proposed a BSS-based method, requiring the received signal to be over-sampled, which can realize both blind equalization and blind multi-user detection in the case that all these three interferences coexist simultaneously. The simulation result indicates that this method performs better than RAKE with perfect equalization, especially in lower SIRs.%非同步的直接序列扩频码分复用(DS-CDMA)系统可能同时存在符号间串扰、多址干扰以及外部干扰.将扩频系统普遍存在的外部窄带干扰作为讨论重点,依据函数空间理论,对干扰进行有限维函数空间上的分解,并将基函数作为混合向量,基函数下的坐标作为待恢复源,通过过采样处理,结合DS-CDMA系统多用户检测模型,提出一种基于盲分离的算法.该算法在未知扩频序列以及信道多径的情况下完成盲多用户检测与盲均衡处理,同时实现外部窄带干扰消除,提高系统的干扰容限.仿真结果表明,在不同的信噪比以及信干比条件下,该算法普遍优于带理想均衡器的RAKE接收机,尤其在干扰显著的情况下,能获得更高的增益.
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